Archives For
Memory Forensics

My recent webcast with Jaron Bradley was recorded and a link is available below. If you have been looking for an excuse to get more familiar with Windows PowerShell, have a look.

What Malware? Hunting Command Line Activity

There is a reason hackers use the command line, and it isn’t to impress you with their prowess. Throughout the history of Windows, the command line has left far fewer forensic artifacts than equivalent operations via the GUI. To make matters worse, the transition to Windows 7 and 8 has spread PowerShell throughout the enterprise. While it makes our lives easier as defenders, it does the same for our adversaries. Every time you marvel at the capabilities of PowerShell, you should fear how your adversaries may use that power against you.

In this CrowdCast we have collected tips and tricks from our incident responders describing how they are countering the command line threat. Learn to identify when it is in play, extract commands from memory and network packets, and see what is new on the horizon from Microsoft to make tracking command line activity easier.

SANS recently posted a webcast I recorded on memory forensics. While the presentation is from early 2012, the concepts are solid and this deck was eventually expanded to the full day of memory forensics training present in the updated Forensics 508 course.

Despite being written in 2006, Chris Ries’ paper Inside Windows Rootkits is still surprisingly relevant. About the only thing missing is a discussion of new(er) x64 mitigation techniques like Kernel Mode Code Signing and Kernel Patch Protection (aka PatchGuard). Few resources have explained rootkit internals so simply. As an example, Figure 2 from the paper neatly ties together the rootkit hooking universe:

With Memoryze 3.0, the folks at Mandiant hit their mid-summer goal to roll out memory analysis support for Windows 8 (x86 and x64) and Server 2012 (x64). While support has not yet been rolled into Redline collector scripts, data collected by Memoryze can be loaded and analyzed in the Redline interface. This is no real surprise since Memoryze is the back-end collection and analysis tool that Redline relies upon.

You can dump Windows memory and process your memory image with the following commands (run MemoryDD.bat from a removable device and Process.bat on your forensic box): Continue Reading…

Like many of you, I have been watching the development of memory forensics over the last two years with a sense of awe. It is amazing how far the field has come since the day Chris Betz, George Garner and Robert-Jan Moral won the 2005 DFRWS forensics challenge. Of course, similar to other forensic niches, the majority of progress has been made on Windows memory forensics. There is good reason for this. Memory can be extremely fickle, with layouts and structures changing on a whim. As an example, the symbols file for Windows 7 SP1x86 is 330MB, largely due to it needing to support major changes that can occur in every service pack and patch. The fact that we have free tools such as Volatile Systems Volatility and Mandiant Redline supporting memory images of arbitrary size from (nearly) every modern version of Windows is nothing short of miraculous.

Nowhere is it more obvious how far the memory analysis field has come than looking at the recent innovations in Mac and Linux memory forensics. Examiners of these less popular platforms have had to sit patiently for years as Windows memory forensics moved from being feasible for OS internals experts to being approachable for the masses. Against all odds, Linux memory analysis has recently seen rapid innovations. If support for the various Windows versions came slowly, imagine the complexity posed by the myriad flavors of Linux and the long list of possible kernel versions. It turns out that the Volatility framework is particularly well suited to tackle this Hydra with its abstraction layers facilitating everything from different image formats to swappable OS profiles to rapid plugin development.

In case you missed it over on the SANS Computer Forensics blog, we recently updated our memory forensics cheat sheet. Not a lot has changed other than updating a few parameter options, adding Michael Cohen’s WinPmem (live memory analysis with Volatility!), and reflecting a few of the changes in the upcoming 2.3 Volatility release (including body file format in Jamie Levy’s timeliner plugin)

(click for PDF)

Amanda Stewart at the FireEye blog dissected the PlugX malware remote access tool (RAT). Of particular interest is this beautiful graphic showing the attack progression. With decoys, DLL sideloading, encrypted payloads, process injection, and new payload retrieval, this attack pretty much has it all!

One of the fun things I have been working on is the huge revision of the SANS Forensics 508: Advanced Forensics and Incident Response material. Rob Lee has spent the last ten years building and updating what has become one of the most well-known and respected digital forensics training courses. The golden age of hacking is in full swing and a whole host of new threats have emerged, including state-sponsored espionage (aka APT), hactivism, client-side attacks, and crimeware. Digital forensic investigations have never been more in demand. However, computer intrusion and malware investigations require a very different skill set than the cases seen by the average forensic examiner. Rob saw a great opportunity to update the FOR508 course to train this next generation of forensic professionals. I estimate that at least 60-70% of the course and nearly every exercise is new within the last year. My specific part in the course is writing the new memory forensics day. My forensic experience dates to the late 1990s, and I can’t remember any other advance in the field that has so fundamentally shifted the balance from the bad guys to the good guys. Memory forensics is now a mature discipline and we have a wonderful array of tools available, allowing us to analyze everything from raw memory files to hibernation files to crash dumps to live memory audits. Memory analysis is a game changing skill and we spend a significant part of the new 508 course learning and incorporating the results of that analysis into the broader forensic process.

A year after release, the Malware Analyst’s Cookbook continues to elicit uniformly high praise from the security community. It is one of those rare books that only come around once every few years. The breadth of information covered is staggering, and it makes an excellent reference to return to as your skills develop. If I could make one recommendation, I would encourage readers to not wait to read the last four chapters of the book.

The last quarter of the book covers memory forensic analysis, and it is the definitive resource currently available on the subject (either online or in print). Continue Reading…